A number of alkaloids of diverse structural type and classification have demonstrated profound physiological activity, for example, as anti-tumor, anti-leukemia, or antimalaria agents. We propose to investigate the utility of a nitrone-induced oxidative cyclization approach, as a novel entry into a variety of structural types, concentrating especially on those alkaloids offering promise in the control of certain types of cancer, or promising other dramatic and useful physiological activity. Efforts will be made to adapt the nitrone cyclo-addition approach to the synthesis of the harringtonines, to certain unsaturated Senecio alkaloids, and febrifugine, all of which offer promise as anti-neoplastic agents. We will investigate approaches to certain tropane and lupine alkaloids, some of which have important physiological activity.